Improvement in millstone-dressing machines



v ZSheetsSheet1. J. C. COOKSON & L.- RASTETTER.

MILLS'I'ONE DRESSING-MACHINE.

No. 191,938. Patented June 12,1877.

INVENTORIT. M a,

5 w ATTORNEY;

NVFETERS. PHOTO-LITHOGRAPHER, WASHINGTON. DJZ

UNITED STATES PATENT OFFICE.

JOHN o. oooKsON AND LOUIS EAsTETTEE, 0F FORT WAYNE, INDIANA,

ASSIGNORS TO JOHN OEEE, 0F sAME PLACE.

IMPROVEMENT IN MILLSTONE-DRESSIYNG MACHINES.

Specification forming part of Letters Patentllo. l9L93S, dated June 12,1877; application filed March 31, 1877.

To all whom it may concern Be it known that we, JOHN, C. GOOKSON andLOUIS RASTET'IER, of Fort Wayne, in the county of Allen and State ofIndiana, have invented a new and valuable Improvement inMillstone-Dressing Machines; and we do hereby declare that the followingis a full, clear, and exact description of the construction andoperation of the same, reference being bad to the annexed drawings,making a part of this specification, and to the letters and fignres ofreference marked thereon.

Figure l of the drawings is a representation of a plan view of ourmillstone-dressing machine, and Fig. 2 is a side elevation thereof. Fig.3 is a transverse vertical sectional view, and Figs. 4 and 5 are detailviewsthereof. Fig. 6 is an enlarged central vertical sectional view ofthe tool-holding device, and Fig. 7 is an enlarged view of the drum withthe top removed.

This invention is an improvement on the devices embraced in LettersPatent No. 185,125, dated December 5, 1876. It consists in certainimprovements for more conveniently and effectually securing thedressing-machine to the millstones; also, in certain improvements in themechanism for automatically causing the upper tool-carriage to travelacross the machine, as hereinafter more fully set forth.

In the accompanying drawings, A designates the bed-plate of ourmillstone-dressing machine, and B an extension of the same, whichreachesquite across the stone, and is provided with a curved flat plate, B, atits front end.

The bed-plate A,with its extension, B, in practice,is placed upon thestone to be dressed, so that the eye of the stone lies at or about thejunction of the bed-plate and its extension, which, together, extendentirely across the face of the stone. By this construction severaladvantages are attained, a more extended and firmer bearing is secured,and oscillations of the bed-plate prevented.

The bed-plate, with its extension, also acts as a straight-edge or levelin dressing the stone, its length being equal to or greater than thediameter of the stone to be dressed, and extending entirely across it.

Said bed-plate supports a longitudinal guideway, that may be raised andlowered at Way, and provided with a cross-guideway, F,

'in which runs the upper tool-carriage Gr, carrying the outer verticalcylinder H of the toolholding mechanism. Said cylinder extends downthrough said carriages E and G to the middle opening of the bed-plate.Said upper carriage G is moved backward and forward in said guideway Fby means of a screwtbreaded shaft, I,whicl1 is journaled in a lug, F, onsaid guideway F, and operates a nut, G, on said upper carriage G. Saidshaft is provided at its outer end with a drum, J ,which has adetachable cover" or cap, J, to which is pivoted a spring-pressed cam ordog, K, that bearsagainst the inside of the rimof said drum. When saidcover J is turned in one direction the said dog engages with and turnssaid drum, rotating said screw-threaded shaft,

to said cover or cap J, its base being adaptedto engage, when turned ineither direction, with a small block, j, formed on said cover, therebyturning the latter. This turning is automatically eiiected by theengagement of said hanging arm with a stud,-m, on a verticallyadjustableplate, M, attached to said bed-plate. By the operation of the abovedevices carriage G is caused automatically to pass in its guideway Facross guideway 0 step by step, each outward journey on said guidewaycausing it to move transversely a certain distance. Itis brought back bya crank, N, on said screw-threaded shaft.

Fig. 6 shows, in enlarged detail, the devices for holding the tool. Theouter cylinder H,

already described, is provided near its lower end, on the inside, with astud or guide-pin, h, which sets into a vertical guide-groove on theoutside of an internally screw-threaded toolholder, 0. P designates avertical adjusting rod or shaft, provided with a screw-threaded downwardextension, P, which engages with said internally screw-threadedtool-holder, so as to adjust the same upward or downward, according tothe direction in which the handwheel Q on the upper end of the saidshaft P is turned. The diamond is thus adjusted so as to cut deep orshallow, as desired.

The tool-holder is also automatically adjusted by means of a stud orshort arm, R, which extends outward from rod P through a vertical slot,h, in the upper part of outer cylinder H. Said stud or short arm R isprovided at its outer end with a roller or rounded end, 7', that runs ina guideway or pivoted trough, S. Said guideway S is supported by astandard, T, on carriageguideway F, and may be clamped thereto at anyinclination, so as to automatically raise and lower the dressing-tool assaid roller or end a" of arm R works backward and forward within it.Said toolholder may be held against any such adjustment, and fixed inone position by means of a clamping-screw, U, which works throughcylinder H and bears against adjusting-rod P. This adapts the machine todress straight across the face of the stone without varying the depth ofthe furrows.

Guideway S may be inclined either to the right or left, according to thebevel of the furrows which are to be cut into the face of v the stone.It serves a double function-guiding the tool, as stated, and alsosupporting the same with the tool-holder and adjusting shaft or rod. Thespring employed for supporting said parts in the previously-patenteddevice of 0rd, Oookson and Rastetter is thereby made superfluous.

What we claim as new, and desire to secure by Letters Patent, is-

1. In a millstone-dressing machine, the bedplate A, provided with theextension B, having the curved flat plate B, flush with the lower faceof the bed-plate, substantially as described, and for the purpose setforth.

2. The combination of cylinder H, having guide-stud h, groovedscrewthreaded tool- .holder 0, adjusting-rod P, provided with the arm R,having roller 1', and guideway S, substantially as and for the purposeset forth.

3. The combination of cylinder El, having guide-stud h, groovedscrew-threaded toolholder 0, adjusting-rod P, arm R, guideway S, andclamping-screw U, substantially as described, and for the purpose setforth.

4. The combination of cylinder H, having guide-stud h, with groovedscrew-threaded tool-holder O and adjusting rod or shaft 1?,substantially as and for the purpose set forth.

5. In a millstone-dressing machine, the combination of the lowerguideway pivoted at one end, with a cam-shaft journaled across thebedplate below the other end of said guideway, substantially as and forthe purpose set forth.

In testimony that we .claim the above we have hereunto subscribed ournames in the presence of two witnesses.

JOHN C. OOOKSON. LOUIS RASTETTER.

Witnesses:

JAMES E. GRAHAM, MART. V. B. GOTSHALL.

